Re: Smithsonian Air and Space Museum errors

Don Bruns wrote:
> I recently returned from a visit to the Smithsonian's Air and Space Museum
> in Washington DC. While many exhibits were interesting and informative, I
> was disappointed to see a few errors or misleading comments in the still
> displays and especially in the Eistein planetarium program. <snip>
> Another photo says that the lunar Laser Ranging Retroreflector array of
> corner cubes placed by the Apollo 11 astronauts was turned off in 1981.
> How does one turn off a piece of glass?

Here's a couple of articles to email the Museum on the current use of
the "turned-off" Lunar Ranging Experiment:

In August 2005 new Apache Point Observatory Lunar Laser-ranging
Operation (APOLLO) begins operations using the Apollo era lunar
retroreflectors -
http://physics.ucsd.edu/%7Etmurphy/apollo/apollo.html
- including a cool picture of their 2.3 _Watt_ green laser lighting up
the Moon -
http://physics.ucsd.edu/%7Etmurphy/apollo/moonbeam.jpg
in -
http://physics.ucsd.edu/%7Etmurphy/apollo/first_lt.html

The purpose of this experiment to test a violation of the General
Theory of Relavivity - Einstein's Equivalence Principle - predicted by
string theory.

The APOLLO website describes the purpose of the experiment as follows:

"Einstein's Equivalence Principle, . . ., claims that all forms of
mass-energy experience the same acceleration in response to an external
gravitational force. This is to say that the intertial mass and the
gravitational mass are equivalent for any form of mass and/or energy. .
.. . If the earth's gravitational self-energy does not precisely obey
the Equivalence Principle, the orbits of the earth and moon around the
sun would be slightly displaced from one another (think of this as a
modification of Kepler's third law), which would show up as a signal in
our lunar range data. Various string-motivated theories, quintessence,
and other alternatives to General Relativity almost all predict a
violation of the Equivalence Principle at some subtle level."

Not too bad for a "turned-off" piece of equipment apparatus.

A second NASA/JPL article refers to the continous use of the Apollo
lunar retroreflectors in experiments for the last thirty-five years -
http://www.jpl.nasa.gov/news/features.cfm?feature=605

- as does a third Lunar Planetary Institute article -
http://www.lpi.usra.edu/expmoon/Apollo15/A15_Experiments_LRRR.html

My experience with museum curators is that if presented with good
documentation on the facts, they will get around to updating and
correcting their exhibits.

- Canopus56

.

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